diff --git a/apps/backup/cephfs/base/resources.yaml b/apps/backup/cephfs/base/resources.yaml
index 1ccb1ba..6eb1e1c 100644
--- a/apps/backup/cephfs/base/resources.yaml
+++ b/apps/backup/cephfs/base/resources.yaml
@@ -6,8 +6,8 @@ data:
   backup.sh: |
     #!/bin/sh
     set -eu
-    backup_fs=$(stat -f -c %T /backup)
-    source_fs=$(stat -f -c %T /source)
+    backup_fs=$(awk '$2 == "/backup" { print $3; exit }' /proc/mounts)
+    source_fs=$(awk '$2 == "/source" { print $3; exit }' /proc/mounts)
     echo "Backup filesystem: $backup_fs; source filesystem: $source_fs"
     test "$backup_fs" = bcachefs
     test "$source_fs" = ceph
diff --git a/apps/backup/s3/resources.yaml b/apps/backup/s3/resources.yaml
index 3225a21..305326b 100644
--- a/apps/backup/s3/resources.yaml
+++ b/apps/backup/s3/resources.yaml
@@ -20,7 +20,7 @@ data:
   backup.sh: |
     #!/bin/sh
     set -eu
-    backup_fs=$(stat -f -c %T /backup)
+    backup_fs=$(awk '$2 == "/backup" { print $3; exit }' /proc/mounts)
     echo "Backup filesystem: $backup_fs"
     test "$backup_fs" = bcachefs
     endpoint=http://rook-ceph-rgw-my-store.rook-ceph.svc:80